In this 60 Minutes segment “Gay or Straight?” the mother of the young fraternal twins is a lesbian who was artificially inseminated to form a fatherless family. For some reason, I think I had heard this from some source that I cannot now find. The web story on the segment is available on the CBS News website. Dr. Michael Bailey disclosed this information today in response to a question from the audience at the Catholic University of America conference on sexual orientation. The 60 Minutes segment was shown to lead off the day.
While this fact alone does not invalidate potential biological explanations, it does call them into question as the only plausible explanation. In the interests of reporting the facts of the story, CBS News should have at least mentioned the context of the twins existence. Leaving aside this disclosure, ruling out parental influence in this situation flies in the face of what we know about how parents regard and treat fraternal twins. Parents often think of them and rate them on a variety of personality dimensions as more divergent than they actually are. It is entirely conceivable to me that a parent might take any temperamental difference and accentuate it (e.g., at 18 months of age, one twin’s desire for a Barbie while the other wanted a fire truck). This may not have happened routinely, of course I don’t know, but to rule it out requires the discounting of other well-established evidence.